1. Field of the Invention
This invention relates generally to methods of making magnetic heads of disk drives, and more particularly to a method involving a simultaneous damascene-based fabrication of a write coil and an electrical connection to an electrical device (such as a thermal-assist heater).
2. Description of the Related Art
The data storage industry continues to improve or increase the amount of data that can be stored on magnetic disks and to more easily design magnetic heads which can adequately read from and write data to these disks. One promising technique to increase the disk storage capacity is heat-assisted magnetic recording (HAMR), which may also be referred to as optically-assisted magnetic recording or thermally-assisted magnetic recording. Such a technique utilizes a recording medium that can store relatively more data since it has a higher coercivity than other types of conventional media. A higher coercivity, however, means that the platter tends to resist reacting to magnetic fields at typical operating temperatures. Therefore, it is difficult to write data to such media at typical operating temperatures. To sufficiently write data to such high coercivity media, a disk drive needs to heat up a portion of the disk to lower its coercivity as the write head writes data to it.
Techniques to provide a thermal heater in a magnetic write head for assisting in the writing of data, referred to in the present application as a “thermal-assist heater”, have been devised. However, a robust process and design for fabricating an electrical connection to such thermal-assist heaters should not add additional processing steps if possible. A suitable electrical connection process should reduce the possibility of shorting and damage to neighboring components of the magnetic head. As design-points in magnetic heads are in sub-micron dimensions, the available spacing becomes limited accordingly. Thus, the ability to reduce or minimize such undesirable occurrences is important because it will translate into higher device yields during manufacturing. A thoughtful design should consider the path, the location, and the effects of the electrical connection to nearby components during its fabrication and to itself during subsequent processes. Finally, an electrical connection should be fabricated such that it can be incorporated into the fabrication of existing components to minimize increasing the number of processing steps.
Accordingly, what are needed are methods of forming electrical connections in magnetic heads (e.g. connections to thermal-assist heaters) which overcome the shortcomings inherent in present-day methods.